A video tape recorder (VTR) is made to perform recording and/or reproducing in conformity with the helical scanning system such that a head drum composed of a fixed drum and a rotating drum is helically wound with a magnetic tape on the periphery of the head drum to make the magnetic tape run at a constant speed by a capstan, and helically scans the magnetic tape by a magnetic head provided on the rotating drum to. That is, while the magnetic head performs scanning on a diagonal track to the length direction of the magnetic tape, the writing of a signal or the reading of a signal is performed.
Such a VTR is equipped with a supply-side reel table and a take-up side reel table which engage with a supply-side reel for reeling out the magnetic tape and a take-up side reel for taking up the magnetic tape, respectively. Here, each reel table is equipped with corresponding braking means, and performs a braking operation as the need arises, whereby each reel table gives aback tension to the magnetic tape, or blocks an unexpected rotation of the reels to prevents the looseness of the magnetic tape.
A reel brake provided on the supply-side reel table is suitable to perform the on-off operation of the brake in the state where the brake arm thereof is held at the same position. In order to express such a function, it is necessary to mount a brake member on the brake arm, and to make the brake member perform a moving operation between an active position and an inactive position against the brake arm. Moreover, the brake structure composed of a plurality of components including the brake member and the brake arm is needed to be small in shape, and in particular it is preferable to assemble the brake structure to be small in size in the axis line direction of the reel table. On the other hand, in the case where such a brake structure is combined as an assembly, the assembly should be a structure difficult to disassemble. That is, although making to be thin and difficult to disassemble contradicts each other, a braking device having a structure of being thin and difficult to disassemble the assembled state is required.
Moreover, the VTR composed of the magnetic recording and reproducing apparatus using the rotating head drum has the structure in which the magnetic tape is pulled out from a tape cassette to be helically wound around the rotating head drum, and the magnetic tape is made to travel in this state. Hereupon, with the aim of lessening the size in the depth direction, namely the loading direction of the magnetic tape, of the mechanical section of the magnetic recording and reproducing apparatus, the VTR adopts the structure such that the pair of reel tables on which the tape cassette is loaded is mounted on a slide chassis, the tape cassette is made to move in the direction of approaching the rotating drum at the time of loading, and a part of the rotating head drum is made to enter a concave pocket portion formed in the front part of the tape cassette.
In this kind of magnetic recording and reproducing apparatus, since the magnetic tape is pulled out from the inside of the tape cassette while performing the linear skate of the slide chassis, the take-up side reel table is rotated, which holds the reel of the tape cassette wound with the magnetic tape to be pulled out at the time of the pulling out of the magnetic tape. Therefore, in the VTR provided with a braking mechanism turning on and off the braking thereof according to the rotation direction of the take-up side reel table, it is necessary to coercively turn off the brake during the linear skate to remove the limiter resistance of the magnet clutch of the braking mechanism for making the brake free at the time of the completion of the linear skate of the slide chassis. Accordingly, in the case of providing the braking mechanism which switches according to the rotation direction of the reel as mentioned above in the take-up side reel table, a release mechanism making the brake free at the time of the completion of the linear skate is disposed on the main chassis. However, in the case of using such release mechanism, a mechanism performing the coercive release over the distance in which a slide chassis performs a minimum linear skating must be disposed, and the miniaturization of the mechanism section is prevented by such release mechanism.
The present invention is devised in view of such a problem. It is an object of the present invention to provide a recording and reproducing apparatus including a braking mechanism which is thin in the axis line directions of reel tables and is also difficult to disassemble an assembled state, or a braking mechanism including release means which does not prevent the miniaturization of the apparatus.